1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _SCSI_SCSI_HOST_H 3 #define _SCSI_SCSI_HOST_H 4 5 #include <linux/device.h> 6 #include <linux/list.h> 7 #include <linux/types.h> 8 #include <linux/workqueue.h> 9 #include <linux/mutex.h> 10 #include <linux/seq_file.h> 11 #include <linux/blk-mq.h> 12 #include <scsi/scsi.h> 13 14 struct block_device; 15 struct completion; 16 struct module; 17 struct scsi_cmnd; 18 struct scsi_device; 19 struct scsi_target; 20 struct Scsi_Host; 21 struct scsi_transport_template; 22 23 24 #define SG_ALL SG_CHUNK_SIZE 25 26 #define MODE_UNKNOWN 0x00 27 #define MODE_INITIATOR 0x01 28 #define MODE_TARGET 0x02 29 30 /** 31 * enum scsi_timeout_action - How to handle a command that timed out. 32 * @SCSI_EH_DONE: The command has already been completed. 33 * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion. 34 * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command. 35 */ 36 enum scsi_timeout_action { 37 SCSI_EH_DONE, 38 SCSI_EH_RESET_TIMER, 39 SCSI_EH_NOT_HANDLED, 40 }; 41 42 struct scsi_host_template { 43 /* 44 * Put fields referenced in IO submission path together in 45 * same cacheline 46 */ 47 48 /* 49 * Additional per-command data allocated for the driver. 50 */ 51 unsigned int cmd_size; 52 53 /* 54 * The queuecommand function is used to queue up a scsi 55 * command block to the LLDD. When the driver finished 56 * processing the command the done callback is invoked. 57 * 58 * If queuecommand returns 0, then the driver has accepted the 59 * command. It must also push it to the HBA if the scsi_cmnd 60 * flag SCMD_LAST is set, or if the driver does not implement 61 * commit_rqs. The done() function must be called on the command 62 * when the driver has finished with it. (you may call done on the 63 * command before queuecommand returns, but in this case you 64 * *must* return 0 from queuecommand). 65 * 66 * Queuecommand may also reject the command, in which case it may 67 * not touch the command and must not call done() for it. 68 * 69 * There are two possible rejection returns: 70 * 71 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but 72 * allow commands to other devices serviced by this host. 73 * 74 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this 75 * host temporarily. 76 * 77 * For compatibility, any other non-zero return is treated the 78 * same as SCSI_MLQUEUE_HOST_BUSY. 79 * 80 * NOTE: "temporarily" means either until the next command for# 81 * this device/host completes, or a period of time determined by 82 * I/O pressure in the system if there are no other outstanding 83 * commands. 84 * 85 * STATUS: REQUIRED 86 */ 87 enum scsi_qc_status (*queuecommand)(struct Scsi_Host *, 88 struct scsi_cmnd *); 89 90 /* 91 * Queue a reserved command (BLK_MQ_REQ_RESERVED). The .queuecommand() 92 * documentation also applies to the .queue_reserved_command() callback. 93 */ 94 enum scsi_qc_status (*queue_reserved_command)(struct Scsi_Host *, 95 struct scsi_cmnd *); 96 97 /* 98 * The commit_rqs function is used to trigger a hardware 99 * doorbell after some requests have been queued with 100 * queuecommand, when an error is encountered before sending 101 * the request with SCMD_LAST set. 102 * 103 * STATUS: OPTIONAL 104 */ 105 void (*commit_rqs)(struct Scsi_Host *, u16); 106 107 struct module *module; 108 const char *name; 109 110 /* 111 * The info function will return whatever useful information the 112 * developer sees fit. If not provided, then the name field will 113 * be used instead. 114 * 115 * Status: OPTIONAL 116 */ 117 const char *(*info)(struct Scsi_Host *); 118 119 /* 120 * Ioctl interface 121 * 122 * Status: OPTIONAL 123 */ 124 int (*ioctl)(struct scsi_device *dev, unsigned int cmd, 125 void __user *arg); 126 127 128 #ifdef CONFIG_COMPAT 129 /* 130 * Compat handler. Handle 32bit ABI. 131 * When unknown ioctl is passed return -ENOIOCTLCMD. 132 * 133 * Status: OPTIONAL 134 */ 135 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, 136 void __user *arg); 137 #endif 138 139 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 140 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd); 141 142 /* 143 * This is an error handling strategy routine. You don't need to 144 * define one of these if you don't want to - there is a default 145 * routine that is present that should work in most cases. For those 146 * driver authors that have the inclination and ability to write their 147 * own strategy routine, this is where it is specified. Note - the 148 * strategy routine is *ALWAYS* run in the context of the kernel eh 149 * thread. Thus you are guaranteed to *NOT* be in an interrupt 150 * handler when you execute this, and you are also guaranteed to 151 * *NOT* have any other commands being queued while you are in the 152 * strategy routine. When you return from this function, operations 153 * return to normal. 154 * 155 * See scsi_error.c scsi_unjam_host for additional comments about 156 * what this function should and should not be attempting to do. 157 * 158 * Status: REQUIRED (at least one of them) 159 */ 160 int (* eh_abort_handler)(struct scsi_cmnd *); 161 int (* eh_device_reset_handler)(struct scsi_cmnd *); 162 int (* eh_target_reset_handler)(struct scsi_cmnd *); 163 int (* eh_bus_reset_handler)(struct scsi_cmnd *); 164 int (* eh_host_reset_handler)(struct scsi_cmnd *); 165 166 /* 167 * Before the mid layer attempts to scan for a new device where none 168 * currently exists, it will call this entry in your driver. Should 169 * your driver need to allocate any structs or perform any other init 170 * items in order to send commands to a currently unused target/lun 171 * combo, then this is where you can perform those allocations. This 172 * is specifically so that drivers won't have to perform any kind of 173 * "is this a new device" checks in their queuecommand routine, 174 * thereby making the hot path a bit quicker. 175 * 176 * Return values: 0 on success, non-0 on failure 177 * 178 * Deallocation: If we didn't find any devices at this ID, you will 179 * get an immediate call to sdev_destroy(). If we find something 180 * here then you will get a call to sdev_configure(), then the 181 * device will be used for however long it is kept around, then when 182 * the device is removed from the system (or * possibly at reboot 183 * time), you will then get a call to sdev_destroy(). This is 184 * assuming you implement sdev_configure and sdev_destroy. 185 * However, if you allocate memory and hang it off the device struct, 186 * then you must implement the sdev_destroy() routine at a minimum 187 * in order to avoid leaking memory 188 * each time a device is tore down. 189 * 190 * Status: OPTIONAL 191 */ 192 int (* sdev_init)(struct scsi_device *); 193 194 /* 195 * Once the device has responded to an INQUIRY and we know the 196 * device is online, we call into the low level driver with the 197 * struct scsi_device *. If the low level device driver implements 198 * this function, it *must* perform the task of setting the queue 199 * depth on the device. All other tasks are optional and depend 200 * on what the driver supports and various implementation details. 201 * 202 * Things currently recommended to be handled at this time include: 203 * 204 * 1. Setting the device queue depth. Proper setting of this is 205 * described in the comments for scsi_change_queue_depth. 206 * 2. Determining if the device supports the various synchronous 207 * negotiation protocols. The device struct will already have 208 * responded to INQUIRY and the results of the standard items 209 * will have been shoved into the various device flag bits, eg. 210 * device->sdtr will be true if the device supports SDTR messages. 211 * 3. Allocating command structs that the device will need. 212 * 4. Setting the default timeout on this device (if needed). 213 * 5. Anything else the low level driver might want to do on a device 214 * specific setup basis... 215 * 6. Return 0 on success, non-0 on error. The device will be marked 216 * as offline on error so that no access will occur. If you return 217 * non-0, your sdev_destroy routine will never get called for this 218 * device, so don't leave any loose memory hanging around, clean 219 * up after yourself before returning non-0 220 * 221 * Status: OPTIONAL 222 */ 223 int (* sdev_configure)(struct scsi_device *, struct queue_limits *lim); 224 225 /* 226 * Immediately prior to deallocating the device and after all activity 227 * has ceased the mid layer calls this point so that the low level 228 * driver may completely detach itself from the scsi device and vice 229 * versa. The low level driver is responsible for freeing any memory 230 * it allocated in the sdev_init or sdev_configure calls. 231 * 232 * Status: OPTIONAL 233 */ 234 void (* sdev_destroy)(struct scsi_device *); 235 236 /* 237 * Before the mid layer attempts to scan for a new device attached 238 * to a target where no target currently exists, it will call this 239 * entry in your driver. Should your driver need to allocate any 240 * structs or perform any other init items in order to send commands 241 * to a currently unused target, then this is where you can perform 242 * those allocations. 243 * 244 * Return values: 0 on success, non-0 on failure 245 * 246 * Status: OPTIONAL 247 */ 248 int (* target_alloc)(struct scsi_target *); 249 250 /* 251 * Immediately prior to deallocating the target structure, and 252 * after all activity to attached scsi devices has ceased, the 253 * midlayer calls this point so that the driver may deallocate 254 * and terminate any references to the target. 255 * 256 * Note: This callback is called with the host lock held and hence 257 * must not sleep. 258 * 259 * Status: OPTIONAL 260 */ 261 void (* target_destroy)(struct scsi_target *); 262 263 /* 264 * If a host has the ability to discover targets on its own instead 265 * of scanning the entire bus, it can fill in this function and 266 * call scsi_scan_host(). This function will be called periodically 267 * until it returns 1 with the scsi_host and the elapsed time of 268 * the scan in jiffies. 269 * 270 * Status: OPTIONAL 271 */ 272 int (* scan_finished)(struct Scsi_Host *, unsigned long); 273 274 /* 275 * If the host wants to be called before the scan starts, but 276 * after the midlayer has set up ready for the scan, it can fill 277 * in this function. 278 * 279 * Status: OPTIONAL 280 */ 281 void (* scan_start)(struct Scsi_Host *); 282 283 /* 284 * Fill in this function to allow the queue depth of this host 285 * to be changeable (on a per device basis). Returns either 286 * the current queue depth setting (may be different from what 287 * was passed in) or an error. An error should only be 288 * returned if the requested depth is legal but the driver was 289 * unable to set it. If the requested depth is illegal, the 290 * driver should set and return the closest legal queue depth. 291 * 292 * Status: OPTIONAL 293 */ 294 int (* change_queue_depth)(struct scsi_device *, int); 295 296 /* 297 * This functions lets the driver expose the queue mapping 298 * to the block layer. 299 * 300 * Status: OPTIONAL 301 */ 302 void (* map_queues)(struct Scsi_Host *shost); 303 304 /* 305 * SCSI interface of blk_poll - poll for IO completions. 306 * Only applicable if SCSI LLD exposes multiple h/w queues. 307 * 308 * Return value: Number of completed entries found. 309 * 310 * Status: OPTIONAL 311 */ 312 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num); 313 314 /* 315 * Check if scatterlists need to be padded for DMA draining. 316 * 317 * Status: OPTIONAL 318 */ 319 bool (* dma_need_drain)(struct request *rq); 320 321 /* 322 * This function determines the BIOS parameters for a given 323 * harddisk. These tend to be numbers that are made up by 324 * the host adapter. Parameters: 325 * size, device, list (heads, sectors, cylinders) 326 * 327 * Status: OPTIONAL 328 */ 329 int (* bios_param)(struct scsi_device *, struct gendisk *, 330 sector_t, int []); 331 332 /* 333 * This function is called when one or more partitions on the 334 * device reach beyond the end of the device. 335 * 336 * Status: OPTIONAL 337 */ 338 void (*unlock_native_capacity)(struct scsi_device *); 339 340 /* 341 * Can be used to export driver statistics and other infos to the 342 * world outside the kernel ie. userspace and it also provides an 343 * interface to feed the driver with information. 344 * 345 * Status: OBSOLETE 346 */ 347 int (*show_info)(struct seq_file *, struct Scsi_Host *); 348 int (*write_info)(struct Scsi_Host *, char *, int); 349 350 /* 351 * This is an optional routine that allows the transport to become 352 * involved when a scsi io timer fires. The return value tells the 353 * timer routine how to finish the io timeout handling. 354 * 355 * Status: OPTIONAL 356 */ 357 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *); 358 /* 359 * Optional routine that allows the transport to decide if a cmd 360 * is retryable. Return true if the transport is in a state the 361 * cmd should be retried on. 362 */ 363 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd); 364 365 /* This is an optional routine that allows transport to initiate 366 * LLD adapter or firmware reset using sysfs attribute. 367 * 368 * Return values: 0 on success, -ve value on failure. 369 * 370 * Status: OPTIONAL 371 */ 372 373 int (*host_reset)(struct Scsi_Host *shost, int reset_type); 374 #define SCSI_ADAPTER_RESET 1 375 #define SCSI_FIRMWARE_RESET 2 376 377 378 /* 379 * Name of proc directory 380 */ 381 const char *proc_name; 382 383 /* 384 * This determines if we will use a non-interrupt driven 385 * or an interrupt driven scheme. It is set to the maximum number 386 * of simultaneous commands a single hw queue in HBA will accept 387 * excluding internal commands. 388 */ 389 int can_queue; 390 391 /* 392 * This determines how many commands the HBA will set aside 393 * for internal commands. This number will be added to 394 * @can_queue to calculate the maximum number of simultaneous 395 * commands sent to the host. 396 */ 397 int nr_reserved_cmds; 398 399 /* 400 * In many instances, especially where disconnect / reconnect are 401 * supported, our host also has an ID on the SCSI bus. If this is 402 * the case, then it must be reserved. Please set this_id to -1 if 403 * your setup is in single initiator mode, and the host lacks an 404 * ID. 405 */ 406 int this_id; 407 408 /* 409 * This determines the degree to which the host adapter is capable 410 * of scatter-gather. 411 */ 412 unsigned short sg_tablesize; 413 unsigned short sg_prot_tablesize; 414 415 /* 416 * Set this if the host adapter has limitations beside segment count. 417 */ 418 unsigned int max_sectors; 419 420 /* 421 * Maximum size in bytes of a single segment. 422 */ 423 unsigned int max_segment_size; 424 425 unsigned int dma_alignment; 426 427 /* 428 * DMA scatter gather segment boundary limit. A segment crossing this 429 * boundary will be split in two. 430 */ 431 unsigned long dma_boundary; 432 433 unsigned long virt_boundary_mask; 434 435 /* 436 * This specifies "machine infinity" for host templates which don't 437 * limit the transfer size. Note this limit represents an absolute 438 * maximum, and may be over the transfer limits allowed for 439 * individual devices (e.g. 256 for SCSI-1). 440 */ 441 #define SCSI_DEFAULT_MAX_SECTORS 1024 442 443 /* 444 * True if this host adapter can make good use of linked commands. 445 * This will allow more than one command to be queued to a given 446 * unit on a given host. Set this to the maximum number of command 447 * blocks to be provided for each device. Set this to 1 for one 448 * command block per lun, 2 for two, etc. Do not set this to 0. 449 * You should make sure that the host adapter will do the right thing 450 * before you try setting this above 1. 451 */ 452 short cmd_per_lun; 453 454 /* 455 * Allocate tags starting from last allocated tag. 456 */ 457 bool tag_alloc_policy_rr : 1; 458 459 /* 460 * Track QUEUE_FULL events and reduce queue depth on demand. 461 */ 462 unsigned track_queue_depth:1; 463 464 /* 465 * This specifies the mode that a LLD supports. 466 */ 467 unsigned supported_mode:2; 468 469 /* 470 * True for emulated SCSI host adapters (e.g. ATAPI). 471 */ 472 unsigned emulated:1; 473 474 /* 475 * True if the low-level driver performs its own reset-settle delays. 476 */ 477 unsigned skip_settle_delay:1; 478 479 /* True if the controller does not support WRITE SAME */ 480 unsigned no_write_same:1; 481 482 /* True if the host uses host-wide tagspace */ 483 unsigned host_tagset:1; 484 485 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 486 unsigned queuecommand_may_block:1; 487 488 /* 489 * Countdown for host blocking with no commands outstanding. 490 */ 491 unsigned int max_host_blocked; 492 493 /* 494 * Default value for the blocking. If the queue is empty, 495 * host_blocked counts down in the request_fn until it restarts 496 * host operations as zero is reached. 497 * 498 * FIXME: This should probably be a value in the template 499 */ 500 #define SCSI_DEFAULT_HOST_BLOCKED 7 501 502 /* 503 * Pointer to the SCSI host sysfs attribute groups, NULL terminated. 504 */ 505 const struct attribute_group **shost_groups; 506 507 /* 508 * Pointer to the SCSI device attribute groups for this host, 509 * NULL terminated. 510 */ 511 const struct attribute_group **sdev_groups; 512 513 /* 514 * Vendor Identifier associated with the host 515 * 516 * Note: When specifying vendor_id, be sure to read the 517 * Vendor Type and ID formatting requirements specified in 518 * scsi_netlink.h 519 */ 520 u64 vendor_id; 521 }; 522 523 /* 524 * Temporary #define for host lock push down. Can be removed when all 525 * drivers have been updated to take advantage of unlocked 526 * queuecommand. 527 * 528 */ 529 #define DEF_SCSI_QCMD(func_name) \ 530 enum scsi_qc_status func_name(struct Scsi_Host *shost, \ 531 struct scsi_cmnd *cmd) \ 532 { \ 533 unsigned long irq_flags; \ 534 enum scsi_qc_status rc; \ 535 \ 536 spin_lock_irqsave(shost->host_lock, irq_flags); \ 537 rc = func_name##_lck(cmd); \ 538 spin_unlock_irqrestore(shost->host_lock, irq_flags); \ 539 return rc; \ 540 } 541 542 543 /* 544 * shost state: If you alter this, you also need to alter scsi_sysfs.c 545 * (for the ascii descriptions) and the state model enforcer: 546 * scsi_host_set_state() 547 */ 548 enum scsi_host_state { 549 SHOST_CREATED = 1, 550 SHOST_RUNNING, 551 SHOST_CANCEL, 552 SHOST_DEL, 553 SHOST_RECOVERY, 554 SHOST_CANCEL_RECOVERY, 555 SHOST_DEL_RECOVERY, 556 }; 557 558 struct Scsi_Host { 559 /* 560 * __devices is protected by the host_lock, but you should 561 * usually use scsi_device_lookup / shost_for_each_device 562 * to access it and don't care about locking yourself. 563 * In the rare case of being in irq context you can use 564 * their __ prefixed variants with the lock held. NEVER 565 * access this list directly from a driver. 566 */ 567 struct list_head __devices; 568 struct list_head __targets; 569 570 struct list_head starved_list; 571 572 spinlock_t default_lock; 573 spinlock_t *host_lock; 574 575 struct mutex scan_mutex;/* serialize scanning activity */ 576 577 struct list_head eh_abort_list; 578 struct list_head eh_cmd_q; 579 struct task_struct * ehandler; /* Error recovery thread. */ 580 struct completion * eh_action; /* Wait for specific actions on the 581 host. */ 582 wait_queue_head_t host_wait; 583 const struct scsi_host_template *hostt; 584 struct scsi_transport_template *transportt; 585 586 struct kref tagset_refcnt; 587 struct completion tagset_freed; 588 /* Area to keep a shared tag map */ 589 struct blk_mq_tag_set tag_set; 590 591 atomic_t host_blocked; 592 593 unsigned int host_failed; /* commands that failed. 594 protected by host_lock */ 595 unsigned int host_eh_scheduled; /* EH scheduled without command */ 596 597 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */ 598 599 /* next two fields are used to bound the time spent in error handling */ 600 int eh_deadline; 601 unsigned long last_reset; 602 603 604 /* 605 * These three parameters can be used to allow for wide scsi, 606 * and for host adapters that support multiple busses 607 * The last two should be set to 1 more than the actual max id 608 * or lun (e.g. 8 for SCSI parallel systems). 609 */ 610 unsigned int max_channel; 611 unsigned int max_id; 612 u64 max_lun; 613 614 /* 615 * This is a unique identifier that must be assigned so that we 616 * have some way of identifying each detected host adapter properly 617 * and uniquely. For hosts that do not support more than one card 618 * in the system at one time, this does not need to be set. It is 619 * initialized to 0 in scsi_host_alloc. 620 */ 621 unsigned int unique_id; 622 623 /* 624 * The maximum length of SCSI commands that this host can accept. 625 * Probably 12 for most host adapters, but could be 16 for others. 626 * or 260 if the driver supports variable length cdbs. 627 * For drivers that don't set this field, a value of 12 is 628 * assumed. 629 */ 630 unsigned short max_cmd_len; 631 632 int this_id; 633 634 /* 635 * Number of commands this host can handle at the same time. 636 * This excludes reserved commands as specified by nr_reserved_cmds. 637 */ 638 int can_queue; 639 /* 640 * Number of reserved commands to allocate, if any. 641 */ 642 unsigned int nr_reserved_cmds; 643 644 short cmd_per_lun; 645 short unsigned int sg_tablesize; 646 short unsigned int sg_prot_tablesize; 647 unsigned int max_sectors; 648 unsigned int opt_sectors; 649 unsigned int max_segment_size; 650 unsigned int dma_alignment; 651 unsigned long dma_boundary; 652 unsigned long virt_boundary_mask; 653 /* 654 * In scsi-mq mode, the number of hardware queues supported by the LLD. 655 * 656 * Note: it is assumed that each hardware queue has a queue depth of 657 * can_queue. In other words, the total queue depth per host 658 * is nr_hw_queues * can_queue. However, for when host_tagset is set, 659 * the total queue depth is can_queue. 660 */ 661 unsigned nr_hw_queues; 662 unsigned nr_maps; 663 unsigned active_mode:2; 664 665 /* 666 * Host has requested that no further requests come through for the 667 * time being. 668 */ 669 unsigned host_self_blocked:1; 670 671 /* 672 * Host uses correct SCSI ordering not PC ordering. The bit is 673 * set for the minority of drivers whose authors actually read 674 * the spec ;). 675 */ 676 unsigned reverse_ordering:1; 677 678 /* Task mgmt function in progress */ 679 unsigned tmf_in_progress:1; 680 681 /* Asynchronous scan in progress */ 682 unsigned async_scan:1; 683 684 /* Don't resume host in EH */ 685 unsigned eh_noresume:1; 686 687 /* The controller does not support WRITE SAME */ 688 unsigned no_write_same:1; 689 690 /* True if the host uses host-wide tagspace */ 691 unsigned host_tagset:1; 692 693 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */ 694 unsigned queuecommand_may_block:1; 695 696 /* Host responded with short (<36 bytes) INQUIRY result */ 697 unsigned short_inquiry:1; 698 699 /* The transport requires the LUN bits NOT to be stored in CDB[1] */ 700 unsigned no_scsi2_lun_in_cdb:1; 701 702 /* 703 * Optional work queue to be utilized by the transport 704 */ 705 struct workqueue_struct *work_q; 706 707 /* 708 * Task management function work queue 709 */ 710 struct workqueue_struct *tmf_work_q; 711 712 /* 713 * Value host_blocked counts down from 714 */ 715 unsigned int max_host_blocked; 716 717 /* Protection Information */ 718 unsigned int prot_capabilities; 719 unsigned char prot_guard_type; 720 721 /* legacy crap */ 722 unsigned long base; 723 unsigned long io_port; 724 unsigned char n_io_port; 725 unsigned char dma_channel; 726 unsigned int irq; 727 728 729 enum scsi_host_state shost_state; 730 731 /* ldm bits */ 732 struct device shost_gendev, shost_dev; 733 734 /* 735 * A SCSI device structure used for sending internal commands to the 736 * HBA. There is no corresponding logical unit inside the SCSI device. 737 */ 738 struct scsi_device *pseudo_sdev; 739 740 /* 741 * Points to the transport data (if any) which is allocated 742 * separately 743 */ 744 void *shost_data; 745 746 /* 747 * Points to the physical bus device we'd use to do DMA 748 * Needed just in case we have virtual hosts. 749 */ 750 struct device *dma_dev; 751 752 /* Delay for runtime autosuspend */ 753 int rpm_autosuspend_delay; 754 755 /* 756 * We should ensure that this is aligned, both for better performance 757 * and also because some compilers (m68k) don't automatically force 758 * alignment to a long boundary. 759 */ 760 unsigned long hostdata[] /* Used for storage of host specific stuff */ 761 __attribute__ ((aligned (sizeof(unsigned long)))); 762 }; 763 764 #define class_to_shost(d) \ 765 container_of(d, struct Scsi_Host, shost_dev) 766 767 #define shost_printk(prefix, shost, fmt, a...) \ 768 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a) 769 770 static inline void *shost_priv(struct Scsi_Host *shost) 771 { 772 return (void *)shost->hostdata; 773 } 774 775 int scsi_is_host_device(const struct device *); 776 777 static inline struct Scsi_Host *dev_to_shost(struct device *dev) 778 { 779 while (!scsi_is_host_device(dev)) { 780 if (!dev->parent) 781 return NULL; 782 dev = dev->parent; 783 } 784 return container_of(dev, struct Scsi_Host, shost_gendev); 785 } 786 787 static inline int scsi_host_in_recovery(struct Scsi_Host *shost) 788 { 789 return shost->shost_state == SHOST_RECOVERY || 790 shost->shost_state == SHOST_CANCEL_RECOVERY || 791 shost->shost_state == SHOST_DEL_RECOVERY || 792 shost->tmf_in_progress; 793 } 794 795 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *); 796 extern void scsi_flush_work(struct Scsi_Host *); 797 798 extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int); 799 extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *, 800 struct device *, 801 struct device *); 802 #if defined(CONFIG_SCSI_PROC_FS) 803 struct proc_dir_entry * 804 scsi_template_proc_dir(const struct scsi_host_template *sht); 805 #else 806 #define scsi_template_proc_dir(sht) NULL 807 #endif 808 extern void scsi_scan_host(struct Scsi_Host *); 809 extern int scsi_resume_device(struct scsi_device *sdev); 810 extern int scsi_rescan_device(struct scsi_device *sdev); 811 extern void scsi_remove_host(struct Scsi_Host *); 812 extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); 813 extern int scsi_host_busy(struct Scsi_Host *shost); 814 extern void scsi_host_put(struct Scsi_Host *t); 815 extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum); 816 extern const char *scsi_host_state_name(enum scsi_host_state); 817 extern void scsi_host_complete_all_commands(struct Scsi_Host *shost, 818 enum scsi_host_status status); 819 820 static inline int __must_check scsi_add_host(struct Scsi_Host *host, 821 struct device *dev) 822 { 823 return scsi_add_host_with_dma(host, dev, dev); 824 } 825 826 static inline struct device *scsi_get_device(struct Scsi_Host *shost) 827 { 828 return shost->shost_gendev.parent; 829 } 830 831 /** 832 * scsi_host_scan_allowed - Is scanning of this host allowed 833 * @shost: Pointer to Scsi_Host. 834 **/ 835 static inline int scsi_host_scan_allowed(struct Scsi_Host *shost) 836 { 837 return shost->shost_state == SHOST_RUNNING || 838 shost->shost_state == SHOST_RECOVERY; 839 } 840 841 extern void scsi_unblock_requests(struct Scsi_Host *); 842 extern void scsi_block_requests(struct Scsi_Host *); 843 extern int scsi_host_block(struct Scsi_Host *shost); 844 extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state); 845 846 void scsi_host_busy_iter(struct Scsi_Host *, 847 bool (*fn)(struct scsi_cmnd *, void *), void *priv); 848 849 struct class_container; 850 851 /* 852 * DIF defines the exchange of protection information between 853 * initiator and SBC block device. 854 * 855 * DIX defines the exchange of protection information between OS and 856 * initiator. 857 */ 858 enum scsi_host_prot_capabilities { 859 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */ 860 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */ 861 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */ 862 863 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */ 864 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */ 865 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */ 866 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */ 867 }; 868 869 /* 870 * SCSI hosts which support the Data Integrity Extensions must 871 * indicate their capabilities by setting the prot_capabilities using 872 * this call. 873 */ 874 static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask) 875 { 876 shost->prot_capabilities = mask; 877 } 878 879 static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost) 880 { 881 return shost->prot_capabilities; 882 } 883 884 static inline int scsi_host_prot_dma(struct Scsi_Host *shost) 885 { 886 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION; 887 } 888 889 static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type) 890 { 891 static unsigned char cap[] = { 0, 892 SHOST_DIF_TYPE1_PROTECTION, 893 SHOST_DIF_TYPE2_PROTECTION, 894 SHOST_DIF_TYPE3_PROTECTION }; 895 896 if (target_type >= ARRAY_SIZE(cap)) 897 return 0; 898 899 return shost->prot_capabilities & cap[target_type] ? target_type : 0; 900 } 901 902 static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type) 903 { 904 #if defined(CONFIG_BLK_DEV_INTEGRITY) 905 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION, 906 SHOST_DIX_TYPE1_PROTECTION, 907 SHOST_DIX_TYPE2_PROTECTION, 908 SHOST_DIX_TYPE3_PROTECTION }; 909 910 if (target_type >= ARRAY_SIZE(cap)) 911 return 0; 912 913 return shost->prot_capabilities & cap[target_type]; 914 #endif 915 return 0; 916 } 917 918 /* 919 * All DIX-capable initiators must support the T10-mandated CRC 920 * checksum. Controllers can optionally implement the IP checksum 921 * scheme which has much lower impact on system performance. Note 922 * that the main rationale for the checksum is to match integrity 923 * metadata with data. Detecting bit errors are a job for ECC memory 924 * and buses. 925 */ 926 927 enum scsi_host_guard_type { 928 SHOST_DIX_GUARD_CRC = 1 << 0, 929 SHOST_DIX_GUARD_IP = 1 << 1, 930 }; 931 932 static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type) 933 { 934 shost->prot_guard_type = type; 935 } 936 937 static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost) 938 { 939 return shost->prot_guard_type; 940 } 941 942 extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state); 943 944 #endif /* _SCSI_SCSI_HOST_H */ 945